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Search Results: 1 - 10 of 30 matches for " Hasna Guedah "
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Electric and Spectroscopic Studies of Pulsed Corona Discharges in Nitrogen at Atmospheric Pressure  [PDF]
Alyen Abahazem, Nofel Merbahi, Hasna Guedah, Mohammed Yousfi
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2017, DOI: 10.4236/jasmi.2017.73006
Abstract: This paper is mainly dedicated to the experimental electric and spectroscopic analysis of positive corona discharges in the case of point to plane configuration, generated in nitrogen at atmospheric pressure. The maximum corona current (a few hundreds of mA), the average current (a few μA) and the average propagation velocity (a few 107 cm/s) are analyzed with the variation of the applied voltage (a few kV) and the gap distance (not exceeding 16 mm). By using an ICCD camera, the dynamics of the discharge during the propagation of primary and secondary streamers across the gap distance was analyzed. Spectroscopic study is emphasized in a spectral range from 200 nm up to 500 nm, to determine the important excited species present in the gaseous environment such as the second positive and the first negative systems (SPS and FNS respectively). The identification of the quenching NOγ emission bands is also emphasized.
Experimental Investigation of Effects of Electric Operating Parameters on Pulsed Corona Discharges in Humid Air at Atmospheric Pressure  [PDF]
Hasna Guedah, Alyen Abahazem, Nofel Merbahi, Mohamed Yousfi, Karim Saber, Ahmed Ihlal
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2018, DOI: 10.4236/jasmi.2018.84005
The present work is devoted to electrical and optical study of a point-plane atmospheric pressure corona discharge reactor in humid air powered by pulsed high voltage supply. The corona current and the injected energy are analyzed as a function of several parameters such as applied voltage and humidity rate. Then, investigations based on emission spectroscopy analysis were used in UV range (from 200 nm to about 400 nm). The main observed excited species were the second positive (SPS), the first negative (FNS) systems and OH(A-X) rotational bands. The latter band was used to simulate the rotational temperature (Tr), whereas the N2+ (FNS) band was used to determine the vibrational temperature (Tv). The electron temperature (Te ) is determined from the ratio of line intensities of the spectral bands of both N2+ FNS at 391.4 nm and N2SPS at 394.4 nm. The rotational, vibrational and electronic temperatures are analyzed as a function of above parameters (applied voltage, frequency and hygrometry rate) near the anodic tip. As well we study the axial variation of electronic temperature for a fixed applied voltage at 6.4 kV, frequency at 10 kHz and 100% of humidity. It is found that the rotational, vibrational and electronic temperatures increased with increasing applied voltage, frequency and humidity rate. The increase of rate hygrometry for an inter-electrode distance fixed at 10 mm causes an increase in both the amplitude of the corona current discharge and the energy injected in corona discharge. This is indicative of more intense reactive plasma while increasing hygrometry rate.
Serial Genetic Algorithm Decoder for Low Density Parity Check Codes  [PDF]
Hasna Chaibi
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2015, DOI: 10.4236/ijcns.2015.89034
Abstract: Genetic algorithms are successfully used for decoding some classes of error correcting codes, and offer very good performances for solving large optimization problems. This article proposes a new decoder based on Serial Genetic Algorithm Decoder (SGAD) for decoding Low Density Parity Check (LDPC) codes. The results show that the proposed algorithm gives large gains over sum-product decoder, which proves its efficiency.
A Study of the Relationship between the Taste Sensitivity of Phenylthiocarbamide (PTC) and Blood Pressure (Random Sample from the Students of Qurna College/Basrah-Iraq)  [PDF]
Hasna Amir Mohaus, Asaad Y. Ayied
Journal of Biosciences and Medicines (JBM) , 2018, DOI: 10.4236/jbm.2018.611001
Abstract: The present study aimed to detect the relationship between taste sensitivity of phenylthiocarbamide (PTC) and pressure (systolic and diastolic) among a group of 138 individuals of both sexes (64 males and 74 females), representing a random sample of students and some professors of, aged (20 - 50) years. The study also included the relationship between eating salted foods and their effect on pressure among males and females of tasters and non-tasters of (PTC) substance. The results showed an increase in the proportion of the phenotypic style of tasters compared to non-tasters among males (75%, 25%) and females (77.03%, 22.97%) respectively. The average of systolic pressure was (117.91 mm/Hg, 107.06 mm/Hg) and diastolic (78.22 mm/Hg, 68.71 mm/Hg) among tasters and on-tasters for both sexes respectively. The results showed significant differences in systolic pressure among non-tasters female compared to their counterpart tasters [X2 (DF = 1) 5.783, P ≤ 0.05]. Such an effect doesn’t appear among males. The results showed an increase of non-tasters (66.58%) among those with abnormal blood pressure and (68.42%) of those who consumed salted foods.
Reduction of NOX Gases Using Copper Zeolite Catalyst
Abdallah M. Hasna
Lecture Notes in Engineering and Computer Science , 2009,
Composite Dielectric Heating and Drying: The Computation Process
Abdallah M. Hasna
Lecture Notes in Engineering and Computer Science , 2009,
Microwave Processing Applications in Chemical Engineering: Cost Analysis
A.M. Hasna
Journal of Applied Sciences , 2011,
Abstract: Rising fossil fuel energy costs and climate change have generated increased interest in alternative drying methods. Microwave processing applications chemical engineering industry is one possible substitute. The advantages of using microwave processing applications in chemical engineering can range from improved quality, reduced wastage; unique characteristics induced by "volumetric" heating and increased production. However, irrespective of benefits that would accrue if the solution is put into effect, the final hurdle for industry adoption can only be made with the achievement of a financial return on investment. This study analyses the costs and benefits for implementing microwave systems and presents results for economic parameters used in cost calculations. The calculations method is outlined using a corrugated board case study. Furthermore in the age of green awakening microwave processing is argued to help improve process efficiency by using green electric supply hence reducing CO2 emissions.
Condensation Heat Transfer in Horizontal Non-Circular Microchannels  [PDF]
Hicham El Mghari, Mohamed Asbik, Hasna Louahlia-Gualous
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.59063
Abstract: This investigation contributes to a better understanding of condensation heat transfer in horizontal non-circular microchannels. For this purpose, the conservation equations of mass, momentum and energy have been numerically solved in both phases (liquid and vapor), and all the more, so the film thickness analytical expression has been established. Numerical results relative to variations of the meniscus curvature radius, the condensate film thickness, the condensation length and heat transfer coefficients, are analyzed in terms of the influencing physical and geometrical quantities. The effect of the microchannel shapes on the average Nusselt number is highlighted by studying condensation of steam insquare, rectangular and equilateral triangular microchannels with the same hydraulic diameter of 250 μm.
Hasna Hayati Nur,Dyah Suryani
Jurnal Kesehatan Masyarakat , 2013,
Abstract: Background: Sausage was a snack with raw meat, crushed meat preserved by salting. Nitrate and nitrite salt is one of the preservatives used in meat preservation process to obtain good color and prevent microbial growth. Nitrite as a preservative permitted its use, but keep in mind its use in food in order not to exceed the limits, so it does not negatively impact human health. Permenkes Republic of. 1168/Menkes/Per/X/1999 about food additives limit the maximum use of the preservative nitrite in processed meat product that is equal to 125 mg / kg. Excessive consumption of nitrite can cause harm to the wearer, whether they are direct, ie poisoning, or who are indirect, ie nitrites are carcinogenic. The purpose of this study to determine the content of nitrite in sausages at sausage distributor in the city of Yogyakarta in 2011. Method: The study was descriptive research laboratory test. The object of this study were 5 brand sausage sausage found in a different distributor. Nitrite content analysis conducted by two stages of testing, the test qualitative and quantitative test. Qualitative test performed to determine whether there is content of nitrite in sausages by using reagents sulfanilat acid-?- naftilamina, while the quantitative tests conducted to determine the levels of nitrite contained in the sausage with a spectrophotometer. Data analysis results of research done descriptively and are presented in table and narrative. Results: The study of five brands of sausage on the distributor in the city of Yogyakarta shows that all brands of sausage samples containing nitrite with nitrite levels varied. Conclusion: Of the 5 brands of sausage samples studied, the results showed that one sample had higher levels of nitrite that does not meet the requirements under Decree No. Permenkes. 1168/Menkes/Per/X/1999, namely the brand sausage sample E with higher levels of nitrite of 211.294 mg / kg. Keywords: Analysis, sausage, nitrite
On the evaluation of linear and non-linear models using DNS data of turbulent channel flows
BenSaid, Hasna;Mompean, Gilmar;Naji, Hassane;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2012, DOI: 10.1590/S1678-58782012000400007
Abstract: in this paper, a priori and a posteriori analyses of algebraic linear and non-linear models are carried out in order to compare their ability to predict near wall turbulent flows. tests were done using data from a direct numerical simulation (dns) of a plane channel flow for three reynolds numbers, based on the friction velocity, reτ = 180, reτ = 395 and reτ = 590 . these models include the linear standard k - ε model, the linear v2- f (manceau et al., 2002) and the non-linear model of shih (shih et al., 1995). the results obtained are then compared with the dns data of moser et al. (1999). the comparisons are shown for the mean velocity profile, components of the reynolds stress tensor, the turbulent kinetic energy (k), and the dissipation rate (ε). the results suggest that the v2 - f is an efficient model to capture the turbulent shear stress component of the reynolds stress near wall flows. however, it is unable to predict correctly the level of anisotropy between normal components of the reynolds stress tensor. furthermore, it is shown that the presence of non-linear terms in a turbulent model improves the ability to predict the anisotropy
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